In a manufacturing process for a circuit board having a conductive pattern formed thereon, it is necessary to inspect the presence of a defect, such as disconnection or short circuit, in the conductive pattern formed on the circuit board.
Heretofore, as a technique for inspecting a conductive pattern, there has been known a contact (pin contact) technique which comprises binging a plurality of pins into contact with first and second opposite ends of a conductive pattern, supplying an electric signal from the pins in contact with the first end to the conductive pattern, and receiving the electric signal from the pins in contact with the second end, so as to inspect continuity or other quality factor of the conductive pattern, as disclosed, for example, in the following Patent Publication 1. In this technique, a certain current serving as the electric signal is supplied to the conductive pattern from a plurality of metal pin probes which are put on respective end terminals of the conductive pattern.
The pin contact technique based on the pin probe set in direct contact with the end terminals has an advantage of being able to achieve a high S/N ratio.                Patent Publication 1: Japanese Patent Laid-Open Publication No. 62-269075        
However, the direct contact of the pins is likely to cause a problem about damages in a conductive pattern, particularly in a circuit wiring pattern formed on a glass board for use in a liquid-crystal display panel, which has a small pattern thickness and a low fixing strength relative to the board.
Further, in an inspection of an electronic component, such as a liquid-crystal panel for portable phones, where the wiring pitch of a conductive pattern becomes finer and finer, a number of pin probes having a fine pitch have to be prepared by consuming a great deal of time and cost.
In addition, the pin probe set has to be newly prepared for each circuit board (inspection target) having a conductive pattern different in configuration. This leads to increase in inspection cost, resulting in major hindrance to cost reduction of electronic components.
Particularly, when a plurality of wiring patterns are not formed independently but connected with each other, as in wiring patterns for use in a liquid-crystal panel, many of the conductive patterns are in a short-circuited state from a circuitry standpoint. Thus, any appropriate inspection apparatus for this type of circuit pattern has not been put into practical use.